SYNTHESES AND STRUCTURE OF 3,3-DIORGANYL- XA-1,5-DITHIA-1,1,5,5-TETRAOXID-3-SILACYCLOHEXANES AND A-1,5-DITHIA-1,1,5,5-TETRAOXID-3-SILACYCLOHEPTANES

Reactions of di-silver-1,n-alkanedisulfonates 1a (n = 1) and 1b (n = 2 ) with Cl(2)SiR(1)R(2) lead to the monomerie xa-1,5-dithia-1,1,5,5-tet raoxid-3-silacyclohexanes (for n = 1) 2a (R(1) = R(2) = Me), 3a (R(1) = Me and R(2) = Ph) and 4a (R(1) = R(2) = Ph) and -heptanes (for n = 2 ) 2b (R(1) = R(2) = Me), 3b (R(1) = Me and R(2) = Ph) and 4b (R(1) = R (2) = Ph). In the case of 2a-4a a competition reaction is observed lea ding to the dimerization products 5a (R(1) = Me and R(2) = Me), 6a (R( 1) = Me and R(2) = Ph) and 7a (R(1) = Ph and R(2) = Ph). The six-membe red ring-systems of 2a-4a are compared with related silanes. An X-ray structure analysis is performed for the xa-1,5-dithia-1,1,5,5-tetraoxi d-3-silacycloheptane (4b).